linux/net/sched/act_ife.c
Eric Dumazet 44c23d7159 net/sched: act_ife: initalize ife->metalist earlier
It seems better to init ife->metalist earlier in tcf_ife_init()
to avoid the following crash :

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10483 Comm: syz-executor216 Not tainted 5.5.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:_tcf_ife_cleanup net/sched/act_ife.c:412 [inline]
RIP: 0010:tcf_ife_cleanup+0x6e/0x400 net/sched/act_ife.c:431
Code: 48 c1 ea 03 80 3c 02 00 0f 85 94 03 00 00 49 8b bd f8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 67 e8 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 5c 03 00 00 48 bb 00 00 00 00 00 fc ff df 48 8b
RSP: 0018:ffffc90001dc6d00 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffffffff864619c0 RCX: ffffffff815bfa09
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000
RBP: ffffc90001dc6d50 R08: 0000000000000004 R09: fffff520003b8d8e
R10: fffff520003b8d8d R11: 0000000000000003 R12: ffffffffffffffe8
R13: ffff8880a79fc000 R14: ffff88809aba0e00 R15: 0000000000000000
FS:  0000000001b51880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563f52cce140 CR3: 0000000093541000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcf_action_cleanup+0x62/0x1b0 net/sched/act_api.c:119
 __tcf_action_put+0xfa/0x130 net/sched/act_api.c:135
 __tcf_idr_release net/sched/act_api.c:165 [inline]
 __tcf_idr_release+0x59/0xf0 net/sched/act_api.c:145
 tcf_idr_release include/net/act_api.h:171 [inline]
 tcf_ife_init+0x97c/0x1870 net/sched/act_ife.c:616
 tcf_action_init_1+0x6b6/0xa40 net/sched/act_api.c:944
 tcf_action_init+0x21a/0x330 net/sched/act_api.c:1000
 tcf_action_add+0xf5/0x3b0 net/sched/act_api.c:1410
 tc_ctl_action+0x390/0x488 net/sched/act_api.c:1465
 rtnetlink_rcv_msg+0x45e/0xaf0 net/core/rtnetlink.c:5424
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:659
 ____sys_sendmsg+0x753/0x880 net/socket.c:2330
 ___sys_sendmsg+0x100/0x170 net/socket.c:2384
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 11a94d7fd8 ("net/sched: act_ife: validate the control action inside init()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-17 10:58:15 +01:00

924 lines
20 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* net/sched/ife.c Inter-FE action based on ForCES WG InterFE LFB
*
* Refer to:
* draft-ietf-forces-interfelfb-03
* and
* netdev01 paper:
* "Distributing Linux Traffic Control Classifier-Action
* Subsystem"
* Authors: Jamal Hadi Salim and Damascene M. Joachimpillai
*
* copyright Jamal Hadi Salim (2015)
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
#include <uapi/linux/tc_act/tc_ife.h>
#include <net/tc_act/tc_ife.h>
#include <linux/etherdevice.h>
#include <net/ife.h>
static unsigned int ife_net_id;
static int max_metacnt = IFE_META_MAX + 1;
static struct tc_action_ops act_ife_ops;
static const struct nla_policy ife_policy[TCA_IFE_MAX + 1] = {
[TCA_IFE_PARMS] = { .len = sizeof(struct tc_ife)},
[TCA_IFE_DMAC] = { .len = ETH_ALEN},
[TCA_IFE_SMAC] = { .len = ETH_ALEN},
[TCA_IFE_TYPE] = { .type = NLA_U16},
};
int ife_encode_meta_u16(u16 metaval, void *skbdata, struct tcf_meta_info *mi)
{
u16 edata = 0;
if (mi->metaval)
edata = *(u16 *)mi->metaval;
else if (metaval)
edata = metaval;
if (!edata) /* will not encode */
return 0;
edata = htons(edata);
return ife_tlv_meta_encode(skbdata, mi->metaid, 2, &edata);
}
EXPORT_SYMBOL_GPL(ife_encode_meta_u16);
int ife_get_meta_u32(struct sk_buff *skb, struct tcf_meta_info *mi)
{
if (mi->metaval)
return nla_put_u32(skb, mi->metaid, *(u32 *)mi->metaval);
else
return nla_put(skb, mi->metaid, 0, NULL);
}
EXPORT_SYMBOL_GPL(ife_get_meta_u32);
int ife_check_meta_u32(u32 metaval, struct tcf_meta_info *mi)
{
if (metaval || mi->metaval)
return 8; /* T+L+V == 2+2+4 */
return 0;
}
EXPORT_SYMBOL_GPL(ife_check_meta_u32);
int ife_check_meta_u16(u16 metaval, struct tcf_meta_info *mi)
{
if (metaval || mi->metaval)
return 8; /* T+L+(V) == 2+2+(2+2bytepad) */
return 0;
}
EXPORT_SYMBOL_GPL(ife_check_meta_u16);
int ife_encode_meta_u32(u32 metaval, void *skbdata, struct tcf_meta_info *mi)
{
u32 edata = metaval;
if (mi->metaval)
edata = *(u32 *)mi->metaval;
else if (metaval)
edata = metaval;
if (!edata) /* will not encode */
return 0;
edata = htonl(edata);
return ife_tlv_meta_encode(skbdata, mi->metaid, 4, &edata);
}
EXPORT_SYMBOL_GPL(ife_encode_meta_u32);
int ife_get_meta_u16(struct sk_buff *skb, struct tcf_meta_info *mi)
{
if (mi->metaval)
return nla_put_u16(skb, mi->metaid, *(u16 *)mi->metaval);
else
return nla_put(skb, mi->metaid, 0, NULL);
}
EXPORT_SYMBOL_GPL(ife_get_meta_u16);
int ife_alloc_meta_u32(struct tcf_meta_info *mi, void *metaval, gfp_t gfp)
{
mi->metaval = kmemdup(metaval, sizeof(u32), gfp);
if (!mi->metaval)
return -ENOMEM;
return 0;
}
EXPORT_SYMBOL_GPL(ife_alloc_meta_u32);
int ife_alloc_meta_u16(struct tcf_meta_info *mi, void *metaval, gfp_t gfp)
{
mi->metaval = kmemdup(metaval, sizeof(u16), gfp);
if (!mi->metaval)
return -ENOMEM;
return 0;
}
EXPORT_SYMBOL_GPL(ife_alloc_meta_u16);
void ife_release_meta_gen(struct tcf_meta_info *mi)
{
kfree(mi->metaval);
}
EXPORT_SYMBOL_GPL(ife_release_meta_gen);
int ife_validate_meta_u32(void *val, int len)
{
if (len == sizeof(u32))
return 0;
return -EINVAL;
}
EXPORT_SYMBOL_GPL(ife_validate_meta_u32);
int ife_validate_meta_u16(void *val, int len)
{
/* length will not include padding */
if (len == sizeof(u16))
return 0;
return -EINVAL;
}
EXPORT_SYMBOL_GPL(ife_validate_meta_u16);
static LIST_HEAD(ifeoplist);
static DEFINE_RWLOCK(ife_mod_lock);
static struct tcf_meta_ops *find_ife_oplist(u16 metaid)
{
struct tcf_meta_ops *o;
read_lock(&ife_mod_lock);
list_for_each_entry(o, &ifeoplist, list) {
if (o->metaid == metaid) {
if (!try_module_get(o->owner))
o = NULL;
read_unlock(&ife_mod_lock);
return o;
}
}
read_unlock(&ife_mod_lock);
return NULL;
}
int register_ife_op(struct tcf_meta_ops *mops)
{
struct tcf_meta_ops *m;
if (!mops->metaid || !mops->metatype || !mops->name ||
!mops->check_presence || !mops->encode || !mops->decode ||
!mops->get || !mops->alloc)
return -EINVAL;
write_lock(&ife_mod_lock);
list_for_each_entry(m, &ifeoplist, list) {
if (m->metaid == mops->metaid ||
(strcmp(mops->name, m->name) == 0)) {
write_unlock(&ife_mod_lock);
return -EEXIST;
}
}
if (!mops->release)
mops->release = ife_release_meta_gen;
list_add_tail(&mops->list, &ifeoplist);
write_unlock(&ife_mod_lock);
return 0;
}
EXPORT_SYMBOL_GPL(unregister_ife_op);
int unregister_ife_op(struct tcf_meta_ops *mops)
{
struct tcf_meta_ops *m;
int err = -ENOENT;
write_lock(&ife_mod_lock);
list_for_each_entry(m, &ifeoplist, list) {
if (m->metaid == mops->metaid) {
list_del(&mops->list);
err = 0;
break;
}
}
write_unlock(&ife_mod_lock);
return err;
}
EXPORT_SYMBOL_GPL(register_ife_op);
static int ife_validate_metatype(struct tcf_meta_ops *ops, void *val, int len)
{
int ret = 0;
/* XXX: unfortunately cant use nla_policy at this point
* because a length of 0 is valid in the case of
* "allow". "use" semantics do enforce for proper
* length and i couldve use nla_policy but it makes it hard
* to use it just for that..
*/
if (ops->validate)
return ops->validate(val, len);
if (ops->metatype == NLA_U32)
ret = ife_validate_meta_u32(val, len);
else if (ops->metatype == NLA_U16)
ret = ife_validate_meta_u16(val, len);
return ret;
}
#ifdef CONFIG_MODULES
static const char *ife_meta_id2name(u32 metaid)
{
switch (metaid) {
case IFE_META_SKBMARK:
return "skbmark";
case IFE_META_PRIO:
return "skbprio";
case IFE_META_TCINDEX:
return "tcindex";
default:
return "unknown";
}
}
#endif
/* called when adding new meta information
*/
static int load_metaops_and_vet(u32 metaid, void *val, int len, bool rtnl_held)
{
struct tcf_meta_ops *ops = find_ife_oplist(metaid);
int ret = 0;
if (!ops) {
ret = -ENOENT;
#ifdef CONFIG_MODULES
if (rtnl_held)
rtnl_unlock();
request_module("ife-meta-%s", ife_meta_id2name(metaid));
if (rtnl_held)
rtnl_lock();
ops = find_ife_oplist(metaid);
#endif
}
if (ops) {
ret = 0;
if (len)
ret = ife_validate_metatype(ops, val, len);
module_put(ops->owner);
}
return ret;
}
/* called when adding new meta information
*/
static int __add_metainfo(const struct tcf_meta_ops *ops,
struct tcf_ife_info *ife, u32 metaid, void *metaval,
int len, bool atomic, bool exists)
{
struct tcf_meta_info *mi = NULL;
int ret = 0;
mi = kzalloc(sizeof(*mi), atomic ? GFP_ATOMIC : GFP_KERNEL);
if (!mi)
return -ENOMEM;
mi->metaid = metaid;
mi->ops = ops;
if (len > 0) {
ret = ops->alloc(mi, metaval, atomic ? GFP_ATOMIC : GFP_KERNEL);
if (ret != 0) {
kfree(mi);
return ret;
}
}
if (exists)
spin_lock_bh(&ife->tcf_lock);
list_add_tail(&mi->metalist, &ife->metalist);
if (exists)
spin_unlock_bh(&ife->tcf_lock);
return ret;
}
static int add_metainfo_and_get_ops(const struct tcf_meta_ops *ops,
struct tcf_ife_info *ife, u32 metaid,
bool exists)
{
int ret;
if (!try_module_get(ops->owner))
return -ENOENT;
ret = __add_metainfo(ops, ife, metaid, NULL, 0, true, exists);
if (ret)
module_put(ops->owner);
return ret;
}
static int add_metainfo(struct tcf_ife_info *ife, u32 metaid, void *metaval,
int len, bool exists)
{
const struct tcf_meta_ops *ops = find_ife_oplist(metaid);
int ret;
if (!ops)
return -ENOENT;
ret = __add_metainfo(ops, ife, metaid, metaval, len, false, exists);
if (ret)
/*put back what find_ife_oplist took */
module_put(ops->owner);
return ret;
}
static int use_all_metadata(struct tcf_ife_info *ife, bool exists)
{
struct tcf_meta_ops *o;
int rc = 0;
int installed = 0;
read_lock(&ife_mod_lock);
list_for_each_entry(o, &ifeoplist, list) {
rc = add_metainfo_and_get_ops(o, ife, o->metaid, exists);
if (rc == 0)
installed += 1;
}
read_unlock(&ife_mod_lock);
if (installed)
return 0;
else
return -EINVAL;
}
static int dump_metalist(struct sk_buff *skb, struct tcf_ife_info *ife)
{
struct tcf_meta_info *e;
struct nlattr *nest;
unsigned char *b = skb_tail_pointer(skb);
int total_encoded = 0;
/*can only happen on decode */
if (list_empty(&ife->metalist))
return 0;
nest = nla_nest_start_noflag(skb, TCA_IFE_METALST);
if (!nest)
goto out_nlmsg_trim;
list_for_each_entry(e, &ife->metalist, metalist) {
if (!e->ops->get(skb, e))
total_encoded += 1;
}
if (!total_encoded)
goto out_nlmsg_trim;
nla_nest_end(skb, nest);
return 0;
out_nlmsg_trim:
nlmsg_trim(skb, b);
return -1;
}
/* under ife->tcf_lock */
static void _tcf_ife_cleanup(struct tc_action *a)
{
struct tcf_ife_info *ife = to_ife(a);
struct tcf_meta_info *e, *n;
list_for_each_entry_safe(e, n, &ife->metalist, metalist) {
list_del(&e->metalist);
if (e->metaval) {
if (e->ops->release)
e->ops->release(e);
else
kfree(e->metaval);
}
module_put(e->ops->owner);
kfree(e);
}
}
static void tcf_ife_cleanup(struct tc_action *a)
{
struct tcf_ife_info *ife = to_ife(a);
struct tcf_ife_params *p;
spin_lock_bh(&ife->tcf_lock);
_tcf_ife_cleanup(a);
spin_unlock_bh(&ife->tcf_lock);
p = rcu_dereference_protected(ife->params, 1);
if (p)
kfree_rcu(p, rcu);
}
static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb,
bool exists, bool rtnl_held)
{
int len = 0;
int rc = 0;
int i = 0;
void *val;
for (i = 1; i < max_metacnt; i++) {
if (tb[i]) {
val = nla_data(tb[i]);
len = nla_len(tb[i]);
rc = load_metaops_and_vet(i, val, len, rtnl_held);
if (rc != 0)
return rc;
rc = add_metainfo(ife, i, val, len, exists);
if (rc)
return rc;
}
}
return rc;
}
static int tcf_ife_init(struct net *net, struct nlattr *nla,
struct nlattr *est, struct tc_action **a,
int ovr, int bind, bool rtnl_held,
struct tcf_proto *tp, u32 flags,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, ife_net_id);
struct nlattr *tb[TCA_IFE_MAX + 1];
struct nlattr *tb2[IFE_META_MAX + 1];
struct tcf_chain *goto_ch = NULL;
struct tcf_ife_params *p;
struct tcf_ife_info *ife;
u16 ife_type = ETH_P_IFE;
struct tc_ife *parm;
u8 *daddr = NULL;
u8 *saddr = NULL;
bool exists = false;
int ret = 0;
u32 index;
int err;
if (!nla) {
NL_SET_ERR_MSG_MOD(extack, "IFE requires attributes to be passed");
return -EINVAL;
}
err = nla_parse_nested_deprecated(tb, TCA_IFE_MAX, nla, ife_policy,
NULL);
if (err < 0)
return err;
if (!tb[TCA_IFE_PARMS])
return -EINVAL;
parm = nla_data(tb[TCA_IFE_PARMS]);
/* IFE_DECODE is 0 and indicates the opposite of IFE_ENCODE because
* they cannot run as the same time. Check on all other values which
* are not supported right now.
*/
if (parm->flags & ~IFE_ENCODE)
return -EINVAL;
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return -ENOMEM;
index = parm->index;
err = tcf_idr_check_alloc(tn, &index, a, bind);
if (err < 0) {
kfree(p);
return err;
}
exists = err;
if (exists && bind) {
kfree(p);
return 0;
}
if (!exists) {
ret = tcf_idr_create(tn, index, est, a, &act_ife_ops,
bind, true, 0);
if (ret) {
tcf_idr_cleanup(tn, index);
kfree(p);
return ret;
}
ret = ACT_P_CREATED;
} else if (!ovr) {
tcf_idr_release(*a, bind);
kfree(p);
return -EEXIST;
}
ife = to_ife(*a);
if (ret == ACT_P_CREATED)
INIT_LIST_HEAD(&ife->metalist);
err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
if (err < 0)
goto release_idr;
p->flags = parm->flags;
if (parm->flags & IFE_ENCODE) {
if (tb[TCA_IFE_TYPE])
ife_type = nla_get_u16(tb[TCA_IFE_TYPE]);
if (tb[TCA_IFE_DMAC])
daddr = nla_data(tb[TCA_IFE_DMAC]);
if (tb[TCA_IFE_SMAC])
saddr = nla_data(tb[TCA_IFE_SMAC]);
}
if (parm->flags & IFE_ENCODE) {
if (daddr)
ether_addr_copy(p->eth_dst, daddr);
else
eth_zero_addr(p->eth_dst);
if (saddr)
ether_addr_copy(p->eth_src, saddr);
else
eth_zero_addr(p->eth_src);
p->eth_type = ife_type;
}
if (tb[TCA_IFE_METALST]) {
err = nla_parse_nested_deprecated(tb2, IFE_META_MAX,
tb[TCA_IFE_METALST], NULL,
NULL);
if (err)
goto metadata_parse_err;
err = populate_metalist(ife, tb2, exists, rtnl_held);
if (err)
goto metadata_parse_err;
} else {
/* if no passed metadata allow list or passed allow-all
* then here we process by adding as many supported metadatum
* as we can. You better have at least one else we are
* going to bail out
*/
err = use_all_metadata(ife, exists);
if (err)
goto metadata_parse_err;
}
if (exists)
spin_lock_bh(&ife->tcf_lock);
/* protected by tcf_lock when modifying existing action */
goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
p = rcu_replace_pointer(ife->params, p, 1);
if (exists)
spin_unlock_bh(&ife->tcf_lock);
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
if (p)
kfree_rcu(p, rcu);
if (ret == ACT_P_CREATED)
tcf_idr_insert(tn, *a);
return ret;
metadata_parse_err:
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
release_idr:
kfree(p);
tcf_idr_release(*a, bind);
return err;
}
static int tcf_ife_dump(struct sk_buff *skb, struct tc_action *a, int bind,
int ref)
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_ife_info *ife = to_ife(a);
struct tcf_ife_params *p;
struct tc_ife opt = {
.index = ife->tcf_index,
.refcnt = refcount_read(&ife->tcf_refcnt) - ref,
.bindcnt = atomic_read(&ife->tcf_bindcnt) - bind,
};
struct tcf_t t;
spin_lock_bh(&ife->tcf_lock);
opt.action = ife->tcf_action;
p = rcu_dereference_protected(ife->params,
lockdep_is_held(&ife->tcf_lock));
opt.flags = p->flags;
if (nla_put(skb, TCA_IFE_PARMS, sizeof(opt), &opt))
goto nla_put_failure;
tcf_tm_dump(&t, &ife->tcf_tm);
if (nla_put_64bit(skb, TCA_IFE_TM, sizeof(t), &t, TCA_IFE_PAD))
goto nla_put_failure;
if (!is_zero_ether_addr(p->eth_dst)) {
if (nla_put(skb, TCA_IFE_DMAC, ETH_ALEN, p->eth_dst))
goto nla_put_failure;
}
if (!is_zero_ether_addr(p->eth_src)) {
if (nla_put(skb, TCA_IFE_SMAC, ETH_ALEN, p->eth_src))
goto nla_put_failure;
}
if (nla_put(skb, TCA_IFE_TYPE, 2, &p->eth_type))
goto nla_put_failure;
if (dump_metalist(skb, ife)) {
/*ignore failure to dump metalist */
pr_info("Failed to dump metalist\n");
}
spin_unlock_bh(&ife->tcf_lock);
return skb->len;
nla_put_failure:
spin_unlock_bh(&ife->tcf_lock);
nlmsg_trim(skb, b);
return -1;
}
static int find_decode_metaid(struct sk_buff *skb, struct tcf_ife_info *ife,
u16 metaid, u16 mlen, void *mdata)
{
struct tcf_meta_info *e;
/* XXX: use hash to speed up */
list_for_each_entry(e, &ife->metalist, metalist) {
if (metaid == e->metaid) {
if (e->ops) {
/* We check for decode presence already */
return e->ops->decode(skb, mdata, mlen);
}
}
}
return -ENOENT;
}
static int tcf_ife_decode(struct sk_buff *skb, const struct tc_action *a,
struct tcf_result *res)
{
struct tcf_ife_info *ife = to_ife(a);
int action = ife->tcf_action;
u8 *ifehdr_end;
u8 *tlv_data;
u16 metalen;
bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb);
tcf_lastuse_update(&ife->tcf_tm);
if (skb_at_tc_ingress(skb))
skb_push(skb, skb->dev->hard_header_len);
tlv_data = ife_decode(skb, &metalen);
if (unlikely(!tlv_data)) {
qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
return TC_ACT_SHOT;
}
ifehdr_end = tlv_data + metalen;
for (; tlv_data < ifehdr_end; tlv_data = ife_tlv_meta_next(tlv_data)) {
u8 *curr_data;
u16 mtype;
u16 dlen;
curr_data = ife_tlv_meta_decode(tlv_data, ifehdr_end, &mtype,
&dlen, NULL);
if (!curr_data) {
qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
return TC_ACT_SHOT;
}
if (find_decode_metaid(skb, ife, mtype, dlen, curr_data)) {
/* abuse overlimits to count when we receive metadata
* but dont have an ops for it
*/
pr_info_ratelimited("Unknown metaid %d dlen %d\n",
mtype, dlen);
qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats));
}
}
if (WARN_ON(tlv_data != ifehdr_end)) {
qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
return TC_ACT_SHOT;
}
skb->protocol = eth_type_trans(skb, skb->dev);
skb_reset_network_header(skb);
return action;
}
/*XXX: check if we can do this at install time instead of current
* send data path
**/
static int ife_get_sz(struct sk_buff *skb, struct tcf_ife_info *ife)
{
struct tcf_meta_info *e, *n;
int tot_run_sz = 0, run_sz = 0;
list_for_each_entry_safe(e, n, &ife->metalist, metalist) {
if (e->ops->check_presence) {
run_sz = e->ops->check_presence(skb, e);
tot_run_sz += run_sz;
}
}
return tot_run_sz;
}
static int tcf_ife_encode(struct sk_buff *skb, const struct tc_action *a,
struct tcf_result *res, struct tcf_ife_params *p)
{
struct tcf_ife_info *ife = to_ife(a);
int action = ife->tcf_action;
struct ethhdr *oethh; /* outer ether header */
struct tcf_meta_info *e;
/*
OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA
where ORIGDATA = original ethernet header ...
*/
u16 metalen = ife_get_sz(skb, ife);
int hdrm = metalen + skb->dev->hard_header_len + IFE_METAHDRLEN;
unsigned int skboff = 0;
int new_len = skb->len + hdrm;
bool exceed_mtu = false;
void *ife_meta;
int err = 0;
if (!skb_at_tc_ingress(skb)) {
if (new_len > skb->dev->mtu)
exceed_mtu = true;
}
bstats_cpu_update(this_cpu_ptr(ife->common.cpu_bstats), skb);
tcf_lastuse_update(&ife->tcf_tm);
if (!metalen) { /* no metadata to send */
/* abuse overlimits to count when we allow packet
* with no metadata
*/
qstats_overlimit_inc(this_cpu_ptr(ife->common.cpu_qstats));
return action;
}
/* could be stupid policy setup or mtu config
* so lets be conservative.. */
if ((action == TC_ACT_SHOT) || exceed_mtu) {
qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
return TC_ACT_SHOT;
}
if (skb_at_tc_ingress(skb))
skb_push(skb, skb->dev->hard_header_len);
ife_meta = ife_encode(skb, metalen);
spin_lock(&ife->tcf_lock);
/* XXX: we dont have a clever way of telling encode to
* not repeat some of the computations that are done by
* ops->presence_check...
*/
list_for_each_entry(e, &ife->metalist, metalist) {
if (e->ops->encode) {
err = e->ops->encode(skb, (void *)(ife_meta + skboff),
e);
}
if (err < 0) {
/* too corrupt to keep around if overwritten */
spin_unlock(&ife->tcf_lock);
qstats_drop_inc(this_cpu_ptr(ife->common.cpu_qstats));
return TC_ACT_SHOT;
}
skboff += err;
}
spin_unlock(&ife->tcf_lock);
oethh = (struct ethhdr *)skb->data;
if (!is_zero_ether_addr(p->eth_src))
ether_addr_copy(oethh->h_source, p->eth_src);
if (!is_zero_ether_addr(p->eth_dst))
ether_addr_copy(oethh->h_dest, p->eth_dst);
oethh->h_proto = htons(p->eth_type);
if (skb_at_tc_ingress(skb))
skb_pull(skb, skb->dev->hard_header_len);
return action;
}
static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a,
struct tcf_result *res)
{
struct tcf_ife_info *ife = to_ife(a);
struct tcf_ife_params *p;
int ret;
p = rcu_dereference_bh(ife->params);
if (p->flags & IFE_ENCODE) {
ret = tcf_ife_encode(skb, a, res, p);
return ret;
}
return tcf_ife_decode(skb, a, res);
}
static int tcf_ife_walker(struct net *net, struct sk_buff *skb,
struct netlink_callback *cb, int type,
const struct tc_action_ops *ops,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, ife_net_id);
return tcf_generic_walker(tn, skb, cb, type, ops, extack);
}
static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index)
{
struct tc_action_net *tn = net_generic(net, ife_net_id);
return tcf_idr_search(tn, a, index);
}
static struct tc_action_ops act_ife_ops = {
.kind = "ife",
.id = TCA_ID_IFE,
.owner = THIS_MODULE,
.act = tcf_ife_act,
.dump = tcf_ife_dump,
.cleanup = tcf_ife_cleanup,
.init = tcf_ife_init,
.walk = tcf_ife_walker,
.lookup = tcf_ife_search,
.size = sizeof(struct tcf_ife_info),
};
static __net_init int ife_init_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, ife_net_id);
return tc_action_net_init(net, tn, &act_ife_ops);
}
static void __net_exit ife_exit_net(struct list_head *net_list)
{
tc_action_net_exit(net_list, ife_net_id);
}
static struct pernet_operations ife_net_ops = {
.init = ife_init_net,
.exit_batch = ife_exit_net,
.id = &ife_net_id,
.size = sizeof(struct tc_action_net),
};
static int __init ife_init_module(void)
{
return tcf_register_action(&act_ife_ops, &ife_net_ops);
}
static void __exit ife_cleanup_module(void)
{
tcf_unregister_action(&act_ife_ops, &ife_net_ops);
}
module_init(ife_init_module);
module_exit(ife_cleanup_module);
MODULE_AUTHOR("Jamal Hadi Salim(2015)");
MODULE_DESCRIPTION("Inter-FE LFB action");
MODULE_LICENSE("GPL");